Omeprazole and its therapeutically acceptable alkaline salts are well known inhibitors of gastric acid secretion and anti-ulcer agents. These compounds are sulfoxides and have an asymmetric center at the sulfur atom and, thus, exist as optical isomers or enantiomers. Esomeprazole is the (S)(−) enantiomer of omeprazole.
Omeprazole and its therapeutically acceptable alkaline salts are disclosed in EP 000 5129 and EP 124,495, respectively. U.S. Pat. No. 6,162,816 discloses crystalline Form A and crystalline Form B of esomeprazole and characterizes them by X-ray powder diffraction. U.S. Pat. No. 5,693,818 discloses various salts of omeprazole enantiomers, including esomeprazole magnesium. U.S. Pat. No. 6,369,085 discloses a particular crystalline form of esomeprazole magnesium trihydrate.
A number of drugs have been found to exhibit desirable dissolution characteristics and, in some cases, desirable bioavailability patterns when used in a specific solid form, e.g., as an amorphous or crystalline solid. Therefore, there is a continuing need for new solid forms of esomeprazole and methods of their preparation.